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From: Paul Rubin <no.email@nospam.invalid>
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Subject: Re: How to get Ada to ?cross the chasm??
Date: Mon, 07 May 2018 21:19:44 -0700
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gautier_niouzes@hotmail.com writes:
> The Zip format is system-agnostic (shameless plug :
> https://unzip-ada.sourceforge.io/ )

Nice, I'll check that out.

> You are shifting again the subject: the point was to understand with a
> simple example how you can use Ada's unconstrained types without
> accumulating garbage...

There's no issue of accumulating garbage in that example because it's
all stack-allocated data.  Garbage becomes relevant when you allocate
objects that have pointers to other allocated objects, and the objects'
lifetimes aren't known in advance.  The CBSG avoids creating pointers by
copying strings around repeatedly when building large strings from
shorter ones.  Even still though, the allocation and access pattern is
simple enough that stack management suffices.

Fwiw, the CBSG's memory consumption is not guaranteed to be bounded
because there is no limit on the possible recursion depth, but that's
unlikely to be a problem in practice since the probability decreases
exponentially with the depth.  And one could always add an explicit
limit.